Sure the movie took place in the 70s but the people the movie was about were adults of 30+ and would not have been listening to The Rolling Stones et al. People in that age group would have been into easy listening like Burt Bacharach, Sinatra, etc. People over 30 had great disdain for 'longhair hippie music'.
shareIt would have been better suited to the vegas theme too.
shareThe music helps establish the time, and Marty did the same thing with GoodFellas.
And people in their 40s were totally grooving to the Stones. The band had been around for over a decade. Remember this is the 1970s, when rock was normal music and filled the airwaves. Nobody considered the Stones longhair hippie music.
For me the music felt right for the themes not the era. Anyone who knows film and music can know this.
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